Staff Engineer - Ruby | EU; remote

Staff Engineer - Ruby | UK & EU (remote)

At Cleo, we’re not just building another fintech app. We’re embarking on a mission to fundamentally change humanity’s relationship with money. Imagine a world where everyone, regardless of background or income, has access to a hyper‑intelligent financial advisor in their pocket. That’s the future we’re creating.

Cleo is a rare success story: a profitable, fast‑growing unicorn with over $300 million in ARR and growing over 2x year‑over‑year. This isn’t just a job; it’s a chance to join a team of brilliant, driven individuals who are passionate about making a real difference. We have an exceptionally high bar for talent, seeking individuals who are not only at the top of their field but also embody our culture of collaboration and positive impact.

If you’re driven by complex challenges that push your expertise, the chance to shape something truly transformative, and the potential to share in Cleo’s success as we scale, while growing alongside a company that’s scaling fast, this might be your perfect fit.

• Acting as a Staff IC across a pillar
  , shaping technical direction and driving delivery across multiple squads
• Partnering with senior peers to define architecture and lead complex, high‑impact initiatives
• Bringing teams together to ship ambitious product work that improves users’ financial health
• Building shared systems, patterns, and tooling that raise the bar across engineering
• Staying hands‑on in our Ruby on Rails monolith — designing APIs, data models, and scalable services
• Anticipating risks and opportunities early
  , influencing plans and technical strategy
• Mentoring engineers and TLs,
  growing the next generation of technical leaders

• You’re excited by the opportunity to own and influence technical direction at a pillar level
• You’ve operated at senior/staff level across multiple teams or complex domains
• You bring strong technical judgment and think in long‑term, scalable solutions
• You’re comfortable leading without authority and aligning teams around a shared direction
• You have a track record of building systems and practices used beyond your immediate team
• You enjoy mentoring and raising the bar for others
• You have strong, hands‑on experience with Ruby on Rails (essential)
• You’re based in the UK or Europe; we hire hybrid & remote in the UK & fully remotely across the EU. We love distributed teams.
  For this role, we’re ideally looking for candidates based within one hour either side of London time, to keep collaboration smooth and calendars sane.

Cleo is built as a Ruby on Rails monolith with a single React Native app frontend, utilising Type Script. We also leverage Python for machine learning services and Postgre

SQL for our database, all hosted on AWS. Our CI/CD pipeline is fully automated, with production deployments happening on every merge via Kubernetes. Our backend engineers deploy multiple times a week, and we release our frontend app to Google and Apple for review at least once a week.

While we take a pragmatic approach, we place a strong emphasis on quality. Our code is peer‑reviewed, and we maintain automated testing using Minitest and Circle

CI. We’re also actively working towards a more modular architecture, focusing on separating concerns to achieve all the benefits of microservices within a monolith, while progressively refactoring our code as we build new features. Everyone in the engineering team contributes to driving our technical strategy, voices & ideas from all levels are valued: we are all owners at Cleo.

• A competitive compensation package (base + equity) with 3 annual reviews, aligned to our termly OKR planning cycles
  . You can view our public progression framework and salary bandings here:
• Work at one of the fastest‑growing tech startups, backed by top VC firms, Balderton & EQT Ventures
• A clear progression plan. We want you to keep growing. That means trying new things, leading others, challenging the status quo and owning your impact. Always with our complete support.
• Flexibility
  . We can’t fight for the world’s financial health if we’re not healthy…